The breast cancer has been one of major cancer diseases leading death for a long time. It can effectively reduce menace of breast cancer by detecting breast cancer early and monitoring the effect of chemotherapy completely. However, there are not any methods achieving the goals effectively. Therefore, it is an important issue to detect the breast cancer early for the health of women.
Images generate by medical modalities such as X-ray mammograms, MRI images and Ultrasound has the characteristic of showing distinct anatomic features such as nipples and boundaries. These features are easy to distinguish such that they are used as feature points for the transformed models. In contrast, infrared images have less distinct boundaries, therefore it is challenging to detect feature points for image registration and making infrared images alignment a difficult hurdle to cross.
Due to the advantages of non-invasion, non-contact, passivity, non-radiation and the ability of detecting the slight variations of temperature caused by neovascularization, Infrared imaging technique has been developed and employed for assessing chemotherapy treatment response. Serving as a medical imaging modality, the Infra-red (IR) image reveals the heat distribution on the surface of the human body. Cancerous tissues tend to have a higher temperature signature than their surrounding normal tissues, and for this reason, IR image has long been studied in hope to serve as an indicator for cancerous breast tissues. Nevertheless, the usefulness of IR images in detecting breast cancers at a single time is not usually enough to assess the chemotherapy treatment response and early detection due to the physiological and environmental influence on the skin temperature distribution. Alternatively, the IR images in detecting tumors over several time points attempt to determine the malignancy of breast tissues based on the variation of heat pattern.
In the prior art, some methods have been reported to use the whole breast temperature or the temperature on the elected region of the breast IR images as the evaluation index for chemotherapy treatment response (Wirth, M. A., Narhan, J., Gray, D., “Nonrigid mammogram registration using mutual information”, Proc. SPIE. 2002, Vol. 4684, pp. 562-573 and Kostelec, P. J., Weaver, J. B., Healy Jr., D. M., “Multiresolution elastic image registration”, Med. Phys. 1998; 25: 1593-1604). The accuracy of assessing the chemotherapy treatment response for these methods would be effected from the temperature of the normal tissues near the tumor tissues. Besides, there are inhomogeneous and anisotropic soft tissues over the breast so the heat patterns will transform for the posture and the position of the patient changed at different time points. It will add the difference of the analysis process.
Therefore, the inventor thought of the idea of an improvement invention after considering the shortage of the prior art and finally invented the case of “an image registration algorithm for assessing chemotherapy treatment response and early detection”. This present application proposes an image registration method for longitudinal dual spectrum infrared images and except that we can use Dual-Spectrum Heat Pattern Separation (DS-HPS) algorithm (U.S. application Ser. No. 12/965,642, Dec. 10, 2010, filed by the applicant) to quantify the effect of chemotherapy by adding the information of heat changing with time. The effects of chemotherapy on breast cancer are effectively traced and evaluated by using this method. The invention is briefly described as follows.